As shown in Fig. 2b, CC1007 upregulated the expression of Bax and downregulated Bcl-2 protein levels, which was accompanied by the cleavage of caspase-3 and caspase-9, and increased the release of cytochrome C. Surprisingly, low dose of CC1007 (≤1.25 μM) hardly induced BCR-ABL1− pre-B-ALL cells apoptosis and did not influence the expression of apoptosis-regulating molecules even after 7 days of treatment (Fig. 2a–d). This evidence concerns the gene CASP9 and acute lymphoblastic leukemia.